Investigation on
annealing effect in a Suprasil sample and
loss measurements in silicon samples
Elisabetta Cesarini a,b), Gianpietro Cagnoli a,c), Enrico Campagna a,d),
Matteo Lorenzini a,b), Giovanni Losurdo a), Filippo Martelli a,d),
Francesco Piergiovanni a,d) , Flavio Vetrano a,d)
a)
b)
c)
d)
INFN Sez. Firenze
Università di Firenze (Dip. Astronomia e Scienza dello Spazio)
University of Glasgow
Università di Urbino
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
1
Summary
Last ILIAS-GW meeting 26-27 October 2006 we presented:
Q measurement facility
Innovative nodal suspension, designed and realized (GeNS)
Now:
We are measuring the loss angle of different interesting
materials:
•Herasil
•Suprasil (annealed sample, that we are investigating with
surface analysis)
•Silicon (we are trying to calculate the thermoelastic
contribution to fit our measurements)
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
2
Dissipation measurements
on Suprasil samples
Q-value @3469 Hz (lower frequency)
Q-value @7889 Hz (higher frequency)
SAMPLE:
Suprasil 311 disk 75x3 mm
(75x3 mm Suprasil disk and D_sphere= 4.75 mm)
(75x3 mm Suprasil disk and D_sphere= 4.75 mm)
Contact surface (radius 20 mm)
Q-value
+/- 5%) @3469
@7890 Hz
Hz (lower
(higher
frequency)
Q-value(in(inmilions
milions+/-5%)
frequency)
(75x3
Suprasil disk
disk and
andD_sphere=
D_sphere=4.75
4.75mm
(75x3 m m Suprasil
mm
) )
Q value
Q value
Sapphire sphere D= 4.75 mm
1,72E+07
1,17E+071,75E+07
1,75E+07
1,17E+07 1,71E+07
1,17E+071,79E+07
1,22E+07
2,00E+07
1,40E+07 1,74E+07
1,17E+07 1,81E+07
1,24E+07
1,72E+07
1,20E+07
1,11E+07
1,50E+07
1,20E+07
1,75E+07
1,00E+07
1,19E+07
8,00E+06
1,00E+07
6,00E+06
4,00E+06
5,00E+06
30
30
1313
2,00E+06
0,00E+00
0,00E+00
12,2
17,1
17,2
y displacement
[ m
y displacement
[ m]
m m]
y
y
-13
-13
20
20
11,7
00
00
x x
[mm[mm]
]
17,5
11,7
[m m]
-13
-13 [mm]
13
10
10
18,1
12,4
17,5
11,7
-30
-30
-20
-20
00
-10
-10
00
-10
-10
17,4
11,1
-20
-20
10
10
20
20
17,911,7
30
30
7890
3469 Hz
2°
1° Butterfly mode
12,0
17,2
11,9 17,5
4° ILIAS-GWA Annual
Meeting - Tubingen (D), October 8-9, 2007
-30
-30
displacem ent
xx displacem
ent [mm
[mm]]
3
Dissipation measurements
on Suprasil samples
Measurement after
the annealing:
Q(3469Hz)=2·107
First measurement:
Q(3469Hz)=2.7·106
it is smaller by a factor two!!
Anneal
in
FI
samples
air (suggested by S.Penn):
-Raise the oven temperature to
the annealing
point (1120°C for
Similar
samples
Suprasil)
- Cool down to the strain
temperature (1025°C for
Suprasil) with a rate of about 10
degrees per hour
V/S = 1.3875 μm
Taken from Mechanical Loss in Fused Silica
-8
Steveand
Penn wait for
-Turn off the oven
φPenn = 2 · 10
Hobart and William Smith Colleges
cool downLSC
in 24
hours
QPenn = 50 millions
Meeting,
March 2006
LIGO DCC LIGO-G0601 40-00-Z
millions
4° ILIAS-GWA AnnualQ
Meeting
Tubingen
(D), October 8-9, 2007
4
exp = -20
Annealing study
Is the Q value increasing due to
an internal or a surface effect?
Surface Analysis
In collaboration with:
INFN sezione Genova and Università di Genova
counts/s
Ellipsometry and XPS
Binding Energy (eV)
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
5
Dissipation measurements
on silicon samples
Samples:
RESULT SUMMARY
•75x1 mm
•75x3 mm sapphire
sphere (d=4.76 mm)
•75x10 mm sapphire
sphere (d=15-20 mm)
Bad reproducibility of measurements
in different suspensions
CLEANING PROCEDURE
We have to work in a clean
room!!!
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
6
Dissipation measurements
on silicon samples
Q value
vsthe
frequency
Taking into account
only
maximum values …
(75x10 mm silicon disk, sapphire sphere Rc=15 mm)
1,80E+07
Q value14730
vs frequency
Hz 1st butterfly mode
1,60E+07
4,00E+06
50906 Hz 3rd butterfly mode
3,50E+06
1,20E+07
3,00E+06
1,00E+07
Max Q-value
Max Q-value
1,40E+07
(75x3 mm silicon disk, sapphire sphere Rc=4.76 mm)
31551 Hz 2nd butterfly mode
8,00E+06
6,00E+06
4,00E+06
2,50E+06
2,00E+06
1,50E+06
1,00E+06
2,00E+06
5155 Hz 1st butterfly mode
11781 Hz 2nd butterfly mode
0,00E+00
0
5,00E+05
20353 Hz 3r butterfly mode
10000
20000
30000
40000
50000
60000
0,00E+00
frequency [Hz]
0
5000
10000
15000
20000
25000
frequency [Hz]
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
7
Thermoelastic contribution
calculation
Thermoelastic contribution for a disk of finite dimensions
Previous calculations :
How
to solve
the problem
- F. Bondu,
P. Hello,
J.Y. Vinet, of
Phys. Lett A 246 (1998) 227
Liu andin
K.S.
Thorne, Phys. Rev. D 62 (2000) 122002
the-Y.T.
sources
a non-adiabatic
- V. B. for
Braginsky,
M.L. Gorodetski,
S.P. Vyatchanin, Phys Lett. A 264 (1999) 1
condition
a cristalline
material?
ADIABATIC APPROXIMATION:
We wantbytoheat
simulate
The DT is not influenced
fluxesthe vibrations
of the disk with ANSYS, then take
the time derivative of the deformations
and put them in the diffusion heat equation.
What is our idea?
We want to calculate exactly the thermoelastic
contribution without any approximation
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
8
Next work…
1. New surface analysis after the annealing, trying to
understand if the produced effect is internal or superficial.
2. Calculation of the thermoelastic contribution in silicon disks,
without any approximation.
3. New loss measurements of the silicon samples with different
thickness (in collaboration with Jena University).
4. Measurements of mechanical properties of coated samples
suitably altered or damaged.
4° ILIAS-GWA Annual Meeting - Tubingen (D), October 8-9, 2007
9
Thanks for your attention
10